Synchronize Desktops on multiple monitors

justplanenutz wrote:

I have a new MacBook M3 Pro and have an external monitor attached. I also have 2 desktops to help organize my work. On my previous MacBook Pro, Desktops were defined on on monitor and appeared on both. When the screen saver kicked in none of the windows moved. Three finger swipe left/right changed Desktops on both monitors. Very convenient.

The set up on the M3 Mac is different. Desktops have to be defined on each monitor and a three finger swipe left/right only changes the the monitor under the mouse pointer. If I set up a single desktop for both monitors, enabling a three finger swipes to change Desktops on both monitors, all the windows on the external monitor move to the MacBook monitor when the screen saver kicks in.

Is there a setting that synchronizes switching desktops such that swiping left/right on one monitor changes both and preserves window positioning when the screen saver kicks in?

>System Settings>Display

mirroring vs extended (?)

ref: Extend or mirror your Mac desktop across multiple displays